Strain mapping in nanowires

Department of Chemical and Materials Engineering, Arizona State University, Tempe, AZ, USA.
Nanotechnology (Impact Factor: 3.67). 10/2005; 16(10):2365-71. DOI: 10.1088/0957-4484/16/10/062
Source: PubMed

ABSTRACT A method for obtaining detailed two-dimensional strain maps in nanowires and related nanoscale structures has been developed. The approach relies on a combination of lattice imaging by high-resolution transmission electron microscopy and geometric phase analysis of the resulting micrographs using Fourier transform routines. We demonstrate the method for a germanium nanowire grown epitaxially on Si(111) by obtaining the strain components epsilon(xx), epsilon(yy), epsilon(xy), the mean dilatation, and the rotation of the lattice planes. The resulting strain maps are demonstrated to allow detailed evaluation of the strains and loading on nanowires.

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